Adding my own +1. On Thu, Apr 17, 2025 at 10:19 AM Daniel Weeks <dwe...@apache.org> wrote:
> +1 (binding) > > I think this update really helps ensure row ids will be present and > reliable for upgraded tables. Thanks Ryan! > > On Wed, Apr 16, 2025 at 4:09 PM Ryan Blue <rdb...@gmail.com> wrote: > >> Hi everyone, >> >> I’d like to start a vote to incorporate the spec changes in PR 12781 >> <https://github.com/apache/iceberg/pull/12781>. >> >> There are two main changes. First, the current language says that >> upgrading a table to v3 leaves all row IDs null and they are assigned when >> the rows are rewritten for the first time (either to move or modify the >> row). The problem with this is that row IDs are missing until the entire >> table is rewritten, which means that the feature is unreliable. Instead, I >> propose that row IDs are assigned in the first write after upgrading to v3. >> >> In addition to making row IDs more useful, the change to how we upgrade >> tables allows us to simplify the spec with statements like “any added or >> existing data file without first_row_id should be assigned one via >> inheritance” and “any manifest without a first_row_id must be assigned >> one when writing a manifest list”. I think this sets clearer expectations. >> >> Second, I found some issues with the strict way that first_row_id is >> inherited and assigned in the metadata tree. The current wording would >> prevent writers from assigning row IDs to existing data files because >> assignment was strict and only accounted for added files. Instead, I >> propose changing the wording to “must be greater than or equal to” so that >> there is some flexibility, and giving simple examples that are safe, like >> first_row_id >> = last_assigned.first_row_id + last_assigned.added_rows_count + >> last_assigned.existing_rows_count. >> >> Please take a look at the PR and vote in the next 72 hours. >> >> [ ] +1 Add these changes to the spec for v3 row lineage >> [ ] +0 >> [ ] -1 I have questions and/or concerns >> >> Thanks, >> >> Ryan >> >
